The Man Flashcards
Where do the the Seminifous tubules come together? What do they join to here?
What happens at this location?
At the Rete Testis, join to the Epididymis, where Sperm Maturation occurs.
What is the Epidydimis continuous with?
Vas Deferens
The Seminiferous tubules are in compartments, separated by connective tissue.
What encloses the testis and the Seminiferous tubules
The Tunica Albuginea
What surrounds the Tunica Albuginea?
Tunica Vaginalis, a serous membrane (has a parietal and visceral layer)
What is a Hydrocoele?
Fluid accumulation in the pleural cavity of the Tunica Vaginalis
Describe the arterial supply of the testes
Via testicular artery which comes from the abdominal aorta
Describe the venous drainge of the testes
- Via the Pampiniform Plexus (Surrounds artery)
- Divides into the Right and Left testicular veins
- Right TV drains into IVC
- Left TV drains into Left Renal Vein then into IVC
What does the Pampiniform Plexus of Veins do to blood coming to Testes?
Cools arriving blood (To temp slightly below body temp)
What can an obstructed left renal vein lead to?
a Varicocoele
Differ between the lymphatic drainage of the Testes and Scrotum
Testes: Lymph drains to Para-aortic lymph nodes (abdominal aorta)
Scrotum: Lymph drains to Inguinal Lymph nodes (more superficial)
The testis can twist on itself (testicular torsion/ torsion of spermatic cord)
Why is this an emergency?
Blood supply is restricted-> Ischaemia-> Loss of testis
Name and describe the deformity that increases risk of testicular torsion
Bell-Clapper deformity, Body of Epidydimis becomes more transverse than vertical
What COULD happen if one testis is lost? (Remember, testes have immune privilege)
Normally Immune System cant detect testes, but when 1 dies it releases large amounts of antigen which is detected.
The immune system then attacks the other, functioning testis
Describe the how the testes evaginate the abdominal wall
The testes are pulled through the abdominal wall muscles by the Gubernaculum, forming the wall of the spermatic cord surrounding the testis.
Fascia and neurovascular structures are included as well
Outline the contents of the Spermatic cord
- 3 fascial layers
- 3 arteries
- 3 veins
- 3 nerves
- Vas deferens
Name the 3 fascial layers of the spermatic cord (Deep to Superficial)
What abdominal muscles/ fascia are they derived from?
- External Spermatic Fascia, from External Oblique
- Cremasteric Fascia, from Internal Oblique
- Internal Spermatic Fascia, from Transversalis Fascia
Compare the composition of the 3 fascial layers of the spermatic cord
External + Internal Spermatic Fascia- Fibrous
Cremasteric fascia- Contains muscle fibres, making up the Cremaster muscle
What does the Cremaster muscle do?
Regulates the height that testes are sitting at in the scrotum
(E.g on hot day cremaster muscle is relaxed, on cold day cremaster muscle is contracted)
Name the 3 arteries of the Spermatic Cord
- Testicular artery
- Cremasteric artery (feeds Cremaster muscle)
- Artery to the Vas Deferens
Name the 3 veins of the Spermatic cord
- Testicular vein
- Cremaster vein
- Vein of Vas Deferens
Name the 3 nerves of the spermatic cord
- Cremasteric nerve/ Genital branch of Genitofemoral Nerve
- Sympathetics to Vas Deferens (initiate ejaculation)
- Ilioinguinal nerve (not in Spermatic cord)
Name the 5 Neurovascular structures within the Internal Spermatic Fascia
- Testicular artery
- Testicular Vein
- Nerve to Vas
- Artery to Vas
- Vein to Vas
Name the 3 Neurovascular structures within the Cremasteric Fascia
- Cremasteric Artery
- Cremasteric Vein
- Cremasteric Nerve/ Genital branch of Genitofemoral
There is no testicular nerve. Name the nerve outside the External Spermatic Fascia
Ilioinguinal
Which fascial layer is the Vas Deferens within?
What 2 other non-neurovascular structures are within this fascial layer
Internal Spermatic Fascia
- Lymphatics
- Obliterated Processus Vaginalis (solid)
Where does the Vas Deferens join the Ejaculatory Duct?
What is its position relative to the Ureter?
At the prostate
Ureter passes underneath Vas Deferens (Remember, water under the bridge)
(In female ureter passes under uterine artery)
The Seminal Vesicles join the Vas Deferens to form what?
How does this enter urethra?
The ejaculatory ducts pass through Prostate to enter urethra (from the back)
The prostate envelopes the urethra. What happens when prostate enlarges?
(with age or Benign Prostate Hyperplasia)
Urethra gets compressed, so more frequent urination
What zone of prostate enlarges with age and compresses urethra?
Transitional zone
Which zone of prostate tends to enlarge with Cancers?
Which structures enter the prostate here?
Peripheral zone (Posterior to TZ and urethra), where Ejaculatory Duct enters
What volume of ejaculate comes from;
- Seminal vesicles
- Prostate
- Testes
- Bulbourehtral glands (Cowper’s glands)
SV: 65%
P: 25%
T: 10%
BU: 1%
65% of ejaculate comes from Seminal Vesicles.
Describe the secretion and its function
Composition:
- Fuctose based alkaline fluid
Function:
- Nutrition for sperm
- Neutralises acidity of vagina
25% of ejaculate comes from the Prostate.
Describe the secretion
- Milky secretion
- Contains proteolytic enzymes
- Mildly acidic
1% of ejaculate comes from the Bulbourethral glands
This secretion is the Pre-ejaculate
State its functions
- Reduce friction
- Reduce the acidity of the Penile Urethra (In preparation for sperm)
Name 3 Accessory Glands
- Seminal Vesicles
- Prostate
- Bulbourethral glands
Briefly outline how an erection comes about
Vasodilation of penile arterioles initiated by Parasympathetic stimulation (and sympathetic inhibition)
Briefly outline how an erection is terminated
Vasoconstriction initiated by Sympathetic stimulation
Erection initiation and Ejaculation are 2 separate processes. Are they sympathetic or parasympathetic?
“Point and Shoot”
Point- Erection is Parasympathetic
Shoot- Ejaculation is Sympathetic
What is the main Erectile tissue of penis?
What is it attached to and why?
Corpus Cavernosa, attached to bone to help anchor penis
What is the Corpus Spongiosum?
When is it patent?
The expansive tissue through which the urethra travels.
It stays patent for sperm passage during ejaculation
What is the white membrane surrounding the erectile tissue?
What does it do?
The Tunica Albuginea (not to be confused with that of the testes)
It provides shape of penis during erection (holding erectile tissue in right place)
Describe the orientation of collagen fibres in the Tunica Albuginea of the penis
Arranged at right angles to each other;
- One circumferential/ transverse
- One parallel to penile long axis
What is the blood supply of the penis
Internal Pudendal Artery (branch of internal iliac artery)
This artery branches into Dorsal Artery
Describe the condition “Fractured penis” (presents with excruciating pain and swelling)
It is a surgical emergency
- Rupture of Tunica Albuginea (due to excessive bending)
- Causes blood leak from Corpus Cavernosa-> Haematoma
Spermatogenesis occurs in the Seminiferous Tubules of the testes.
What cells form the Seminiferous Tubules? What do they do?
Sertoli cells (Epithelium of tubules)- Spermatogenesis
Leydig cells (In tissue between tubules) - Produce testosterone
Name the 2 different issue types of the Penis
- Corpus Spongiosum
- Corpsu Cavernosum (paired tissue, are 2 of them)